Effect of increasing dietary calcium through supplements and dairy food on body weight and body composition: A meta-analysis of randomised controlled trials

Abstract

This meta-analysis of randomised controlled trials assessed the effect of Ca on body weight and body composition through supplementation or increasing dairy food intake. Forty-one studies met the inclusion criteria (including fifty-one trial arms; thirty-one with dairy foods (n 2091), twenty with Ca supplements (n 2711). Ca intake was approximately 900 mg/d higher in the supplement groups compared with control. In the dairy group, Ca intake was approximately 1300 mg/d. Ca supplementation did not significantly affect body weight (mean change (-0.17, 95 % CI-0.70, 0.37) kg) or body fat (mean change (-0.19, 95 % CI-0.51, 0.13) kg) compared to control. Similarly, increased dairy food intake did not affect body weight (-0.06, 95 % CI-0.54, 0.43) kg or body fat change (-0.36, 95 % CI-0.80, 0.09) kg compared to control. Sub-analyses revealed that dairy supplementation resulted in no change in body weight (nineteen studies, n 1010) (-0.32, 95 % CI-0.93, 0.30 kg, P= 0.31), but a greater reduction in body fat (thirteen studies, n 564) (-0.96, 95 % CI-1.46,-0.46 kg, P < 0.001) in the presence of energy restriction over a mean of 4 months compared to control. Increasing dietary Ca intake by 900 mg/d as supplements or increasing dairy intake to approximately 3 servings daily (approximately 1300 mg of Ca/d) is not an effective weight reduction strategy in adults. There is, however, an indication that approximately 3 servings of dairy may facilitate fat loss on weight reduction diets in the short term.